To survive and reproduce, organisms need to be adapted to their environments. These adaptations can either be:

  • Structural
  • Behavioural
  • Functional

Structural adaptations

Structural adaptations are the physical features that allow an organism to compete. For example, the organism’s shape or colour.

For example, foxes that live in warm regions have long ears, a long tail and wide body surfaces.

This increases the surface area of skin that is exposed to the surroundings. This skin contains warm circulating blood, so more heat is lost to the cooler surroundings.

Behavioural adaptations

Behavioural adaptations are the way an organism behaves or acts, which gives them an advantage.

For example:

  • Some birds migrate to warmer regions during the winter
  • Wolves work together in packs to hunt and kill prey

Functional adaptations

Functional adaptations are processes inside an organism’s body that allow it to compete. For example, camels store fat inside their humps, which they can break down later for energy.

For example, chameleons change colour based on their environment and scenario.

Camouflage is an adaptation that allows chameleons to blend into their surroundings. This helps them to avoid detection by predators.


Extremophiles are organisms that are adapted to live in extreme environments. They are usually in areas with very high or low temperatures, pressures, or high salt concentrations.

The giant tube worm is an extremophile that is found near deep-sea hydrothermal vents. In these areas, the conditions are extremely hot, under high pressure and there is no sunlight. The giant tube worm contains a large number of bacteria in its gut, which convert gases into organic molecules for the worm to eat.

  • These ecosystems are unique because the food chains and webs do not start with photosynthesising plants or algae.

The adaptations of such extremophiles allow them to survive in these locations. However, many extremophiles cannot survive in moderate conditions.